subsystem-bench: add regression tests for availability read and write (#3311)

### What's been done
- `subsystem-bench` has been split into two parts: a cli benchmark
runner and a library.
- The cli runner is quite simple. It just allows us to run `.yaml` based
test sequences. Now it should only be used to run benchmarks during
development.
- The library is used in the cli runner and in regression tests. Some
code is changed to make the library independent of the runner.
- Added first regression tests for availability read and write that
replicate existing test sequences.

### How we run regression tests
- Regression tests are simply rust integration tests without the
harnesses.
- They should only be compiled under the `subsystem-benchmarks` feature
to prevent them from running with other tests.
- This doesn't work when running tests with `nextest` in CI, so
additional filters have been added to the `nextest` runs.
- Each benchmark run takes a different time in the beginning, so we
"warm up" the tests until their CPU usage differs by only 1%.
- After the warm-up, we run the benchmarks a few more times and compare
the average with the exception using a precision.

### What is still wrong?
- I haven't managed to set up approval voting tests. The spread of their
results is too large and can't be narrowed down in a reasonable amount
of time in the warm-up phase.
- The tests start an unconfigurable prometheus endpoint inside, which
causes errors because they use the same 9999 port. I disable it with a
flag, but I think it's better to extract the endpoint launching outside
the test, as we already do with `valgrind` and `pyroscope`. But we still
use `prometheus` inside the tests.

### Future work
* https://github.com/paritytech/polkadot-sdk/issues/3528
* https://github.com/paritytech/polkadot-sdk/issues/3529
* https://github.com/paritytech/polkadot-sdk/issues/3530
* https://github.com/paritytech/polkadot-sdk/issues/3531

---------

Co-authored-by: Alexander Samusev <41779041+alvicsam@users.noreply.github.com>

polkadot/node/subsystem-bench/src/cli/valgrind.rs

@@ -0,0 +1,49 @@
+// Copyright (C) Parity Technologies (UK) Ltd.
+// This file is part of Polkadot.
+
+// Polkadot is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Polkadot is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Polkadot.  If not, see <http://www.gnu.org/licenses/>.
+
+use color_eyre::eyre;
+
+/// Show if the app is running under Valgrind
+pub(crate) fn is_valgrind_running() -> bool {
+	match std::env::var("LD_PRELOAD") {
+		Ok(v) => v.contains("valgrind"),
+		Err(_) => false,
+	}
+}
+
+/// Stop execution and relaunch the app under valgrind
+/// Cache configuration used to emulate Intel Ice Lake (size, associativity, line size):
+///     L1 instruction: 32,768 B, 8-way, 64 B lines
+///     L1 data: 49,152 B, 12-way, 64 B lines
+///     Last-level: 2,097,152 B, 16-way, 64 B lines
+pub(crate) fn relaunch_in_valgrind_mode() -> eyre::Result<()> {
+	use std::os::unix::process::CommandExt;
+	let err = std::process::Command::new("valgrind")
+		.arg("--tool=cachegrind")
+		.arg("--cache-sim=yes")
+		.arg("--log-file=cachegrind_report.txt")
+		.arg("--I1=32768,8,64")
+		.arg("--D1=49152,12,64")
+		.arg("--LL=2097152,16,64")
+		.arg("--verbose")
+		.args(std::env::args())
+		.exec();
+
+	Err(eyre::eyre!(
+		"Сannot run Valgrind, check that it is installed and available in the PATH\n{}",
+		err
+	))
+}